1. Field of the Invention
The present invention relates to a method and system for providing a tile map service and, more particularly, to a method for providing a tile map service, which can effectively transmit, receive, and restore a tile map in a service for transmitting and receiving a large and high-resolution tile map, and a system for the same.
2. Description of the Related Art
A geospatial information service technology is a technology that digitizes a variety of spatial phenomenon information and provides the digitized information to a user such that the user can effectively identify various spatial, physical and social phenomena.
A technique for providing digital map data in the geospatial information service technology typically uses a tile map service. The tile map service means a service that divides original digital map data into a plurality of map tiles in the form of a grid and transmits only map tiles selected from the original digital map data and corresponding to a request from a receiving client such that the receiving client generates the original map data by combining the received map tiles. For example, the receiving client can receive a map service without transmitting large original digital map data in such a manner that only map tiles corresponding to the current location of the user or the point where that the user wishes to move are selected from the original entire map data and transmitted. A representative example of the tile map service includes Google map service provided by Internet portal sites such as Google, etc. Prior art related to the tile map service of Google includes U.S. Patent Publication No. 20100201707 entitled “Digital Mapping System” filed by the same company.
Meanwhile, even in the case of such a tile map service, numerous tile map data are individually generated from the original digital map data, and thus the amount of tile map data itself is increased. Moreover, numerous tile map data corresponding to a map area requested by a client should be transmitted one by one at a time, and thus excessive network access between the client and the server occurs, which is problematic.
To solve such problems, Korean Patent Publication No. 10-2004-0025106 discloses a method of providing map data, in which map data consisting of vector data and image data is divided into a plurality of tile regions in the form of a checkerboard, the vector data and the image data are coded for each tile region and stored in a database, and only tile region data corresponding to a map area requested by a client is transmitted to the client.
However, even when adopting the prior art methods, significant delays in transmitting, receiving, and restoring a map tile including precise image data may occur. In particular, when the user requests a plurality of map areas, it is very difficult to effectively provide geospatial information. That is, when the user moves quickly, for example, significant delays in transmitting, receiving, and restoring precise tile map data may occur, which is problematic.